In the normal state, males make and release into the air a group of sex hormones called "male phermones". In addition, in the normal state in males, a specific set of cells in the male sensory nervous system contain "female phermone receptors" that bind to "female phermones". The same is true in females, females make and release "female phermones", and they have cells in the sensory nervous system that contain "male phermone receptors" that bind to "male phermones". So, we have a very simple system. Males make and release phermones that bind to the cells of the female sensory system that triggers sexual interest in them, and vice versa.

In homosexuality, there is a "mis-wiring" of the system due genetic mutation. Here, males still release male phermone, but the cells in their sensory nervous system express "male phermone receptor". In other words, they respond to "male phermones" rather than "female phermones". The same scenario is true for lesbians. This phenomenon explains why upon reaching sexual maturity, gays and lesbian state how "they feel differently...they've always felt this way". They have no choice, just as a person with MS, Parkinson, ALS, have no choice. It is genetic predisposition.

Agreed, totally dig the hair. You have an interesting theory, but do you have any research to back it up? For example, has anyone identified the genes or pheremone receptors you mention? Also, how would you explain examples of homosexuality that are clearly non-genetic (I cite my prison example again as evidence)?

Generally speaking, the more people talk about "being saved," the further away they actually are from true salvation.

I was just thinking, if homosexuality is genetic, I would think it would be passed on to children. Does anyone know of any statistics relating to how many children of homosexuals also turn out to be homosexual? Specifically, does it show a significantly higher rate of occurence than the general population?

I admit this isn't a valid scientific source, but just judging from homosexuals I know who have children, not a single one of their children is also homosexual. I only know a dozen or so people who fit this category, so I admit it's not a statistically useful sample; I'm just throwing it out there as a thought.

I also think the fact that some people can change their sexual preference indicates a non-genetic cause. Genetics could play a role in certain cases, but I don't think it's the major factor. Culture probably plays a huge role, such as in ancient Greece where homosexuality was expected from most males.

On the cultural/political side of things, it seems to be the current politically correct viewpoint that homosexuality has to be genetic and unchangeable. I'm guessing this is so it would be easier for homosexuals to gain equal rights in society. The truth is, just because something is politically or culturally preferable doesn't matter a rat's hind end if it's correct. The evolution/creation debate is a perfect example. And since we're on the topic, I don't think homosexuality being non-genetic or even changeable gives homosexuals any less right to be treated equally. In my opinion, any sexual eccentricity is perfectly alright as long as the participants are consenting adults. So although a genetic cause might be politically correct, I don't think it should really matter as far as equal rights are concerned.

Generally speaking, the more people talk about "being saved," the further away they actually are from true salvation.

Genes do not have to pass on through the person expressing that gene--although some form will. IF it is a case of certain combination of genes or alleles, then a parent can pass on traits to all the children. So, nieces, nephews, grand-nieces and grand-nephews may eventually express the homosexual trait--if it is in fact a genetic issue. The gene can carry on unexpressed through generations. There are some non-procreating examples for the natural selection theory in evolution. There are also other evolutionary functions out there that might not have to fit into a "perfect" natural selection mechanism. There are other functions in survival such as co-evolution.

READ: Dr. Tatiana's Sex Advice To All Creation, by Olivia Judson. Just look in the index under homosexuality.

I felt slightly concerned that someone on a biology page would confuse socially constructed gender with biological sex. I also think Tatiana will explain that not all sexual behavior in the animal kingdom is for pro-creation. And as we know, it is a quite loaded subject for humans who have used it for emotional connections as well as sport.

Thinking further, I wonder if we should consider the fact that Darwin discussed the function of civilization as a factor in natural selection; that perhaps civilization is maladaptive and thus is not bound to the restrictions or functions of natural selection and the fitness of our offspring to have more offspring. This discussion is valid, even though some fair Spencerian decided to name a concept for the misunderstanding of that section "social Darwinism."

Oh, and homosexual "behavior" seems to be a good name for the activity of the pygmy chimps because they do not have monogamous relationships nor would they mate for life. In humans, homosexuality seems to be a good term because of the social construction of monogamy--if you like the same sex--you may want to stay together for life. But a pygmy chimp would have homosexual encounters and heterosexual encounters. Unless of course the study shows that certain Pygmy Chimps will ONLY have sexual encounters with multiple male partners and never female. . .

This topic has been stagnant a long time i see...but I'm new here and I'm catching up...

This is an interesting subject. It is particularly interesting to me because I am gay. I do believe it is a genetic issue, and I hope that some day there is concrete data to back that up.

On passing the gene a long in a family. Well, there are three homosexuals in my family including myself (including extended family, uncle, nieces, cousins, etc). My partner's family...it is the same case...she is not the only homosexual in her family...there are many. And I know this to be the case in many homosexual families. So, while my little world isn't "proof"...it is certainly enough to get you thinking.

Interesting point, but I wonder how you would respond to examples of homosexuality that are non-genetic related, such as some of the examples that have been mentioned in this thread. I don't doubt that it is possible for genes to be one cause, but I don't think it's the only cause.

Generally speaking, the more people talk about "being saved," the further away they actually are from true salvation.

I know this is an older topic but I'm new here and it caught my attention.

Firstly, I think it is clearly impossible to claim (at this point in time) whether homosexuality is genetically or socially induced. But I do think a clear differentiation between homosexual nature and homosexual practice is needed.

If a man, who has identified himself as heterosexual for the majority of his life - father and husband, engages in a sexual act with another male on a one-off occasion, is he to be called homosexual? I think not. I understand homosexuality, as a sexual orientation, to mean someone who primarily seeks sexual and romantic relations with a member of the same sex.

Therefore in the 'prison case', which has been mentioned before, it is my belief that these encounters are only homosexual in act and not in nature, bred from a situation where no opposite sex member is available to sexually engage with - I agree with the concept of situational sexuality.

I also believe that situational sexuality played a part in Ancient Greece (another area often highlighted, where younger males were sometimes submissive sex partners to older males). Although how widespread this practice was is debatable.

As any sexual orientation is never as clear-cut as our social labels suggest, I would theorize that if homosexuality was genetic there would be varying degrees - like a scale between strictly homosexual and strictly heterosexual, perhaps with social and environmental factors effecting this to some degree.

And so I think homosexuality is more likely a combination of genetic, environmental, and social factors. With genetic factors acting as a base on which environmental and social factors build. So that sexual orientation can be changed to some degree, depending on how strongly a persons orientation has been developed through 'nurture'.

I am new to these forums, and don't have the time to read all of these posts.I only have a simple understanding of evolution and its mechanics, but if homosexuality were genetic, could that not be a mode of population control?

Certain individuals are wired to be attracted to mates to ensure that they no longer procreate, narrowing down the populace and reducing competition?!?